In order to take up the forces exerted on the gear wheel in said prior mounting, two rotary bearings are provided between the drive shaft and the frame to which the motor housing is fixed, said bearings being disposed on either side of the zone in which the gear wheel is disposed. This disposition implies, in particular, that a portion of the shaft should extend beyond the gear wheel in the axial direction in order to support one of said two bearings. The first drawback of this configuration lies in its considerable axial extent, together with the corresponding weight and manufacturing costs; there is also a second major drawback: namely the need to provide two rotary bearings.
Preferred embodiments of the invention remedy this state of affairs, not only in the context of the particular mounting from which the present invention stems, but also in a broader context as defined below.